LS 400 will not start
Thread Starter
Driver School Candidate
Joined: Mar 2009
Posts: 12
Likes: 0
From: Indiana
The firing order is correct. I can see the timing belt as I have taken off the covers to the distributor caps. The belt looks to be in good condition and is tight. This has got me stomped
Rookie
Joined: Sep 2008
Posts: 86
Likes: 0
From: TN
Where did you spray the starting fluid?
I think that all of us have assumed that you sprayed it directly into the throttle body, but you might not have...
If you are getting spark spraying starting fluid directly into the throttle body will get the engine to sputter.
You will need to take your intake plastic tubing completely off to do this. If you still get nothing after spraying the starting fluid directly into the TB then double/triple check your spark plug wiring to make sure you are correct. Do you have the diagram?
http://www.lexls.com/tutorials/ignition/sparkplugs.html
I sincerely doubt that your engine has skipped timing, but stranger things have happened.
Post back your results.
I think that all of us have assumed that you sprayed it directly into the throttle body, but you might not have...
If you are getting spark spraying starting fluid directly into the throttle body will get the engine to sputter.
You will need to take your intake plastic tubing completely off to do this. If you still get nothing after spraying the starting fluid directly into the TB then double/triple check your spark plug wiring to make sure you are correct. Do you have the diagram?
http://www.lexls.com/tutorials/ignition/sparkplugs.html
I sincerely doubt that your engine has skipped timing, but stranger things have happened.
Post back your results.
Thread Starter
Driver School Candidate
Joined: Mar 2009
Posts: 12
Likes: 0
From: Indiana
My motor at this point looks exactly like picture number 16, I had someone press on the gas pedal and spray it in the throttle body, no sputter, no nothing. I checked my firing order yesterday based upon this http://autorepair.about.com/library/...bl-fo-8712.htm ..
Thread Starter
Driver School Candidate
Joined: Mar 2009
Posts: 12
Likes: 0
From: Indiana
I took out each plug and had someone turn the key over and see if it was arcking, they all did. I have not done a compression test on all cylinders, do you know what the compression should be?
Lexus Champion
Joined: Feb 2001
Posts: 3,124
Likes: 32
From: Texas
Have you pulled a spark plug? Plugs could be fouled.
Just because it has spark to the leads does not guarantee spark at the plugs. Combination of fouled plugs and weak coils and or leaky leads could prevent firing. If the valve timing is good and you actually have spark the starter fluid should have at least fired a couple of times. Sounds like no spark in cylinders... pull a plug and inspect, test, replace if needed. Make sure the leads will spark a grounded plug.
Is the timing belt "good" or "new"? If new possibly out of position.
Just because it has spark to the leads does not guarantee spark at the plugs. Combination of fouled plugs and weak coils and or leaky leads could prevent firing. If the valve timing is good and you actually have spark the starter fluid should have at least fired a couple of times. Sounds like no spark in cylinders... pull a plug and inspect, test, replace if needed. Make sure the leads will spark a grounded plug.
Is the timing belt "good" or "new"? If new possibly out of position.
ClubLexus Stories
Celebrating Lexus & Toyota from Around the Globe
10 Lexus Bargains That are Cheaper Than a New Toyota RAV4
Joe Kucinski
8 Weirdest Things Lexus Has Ever Built
Verdad Gallardo
10 Lexus Designs That Have Aged Like Fine Wine
Verdad Gallardo
8 Tips for Improving Your Hybrid or Plug-in Hybrid's Efficiency!
Michael S. Palmer
10 Best Lexus Models No One Remembers
Joe Kucinski
TRD Off-Road Premium: Best 2026 4Runner, Except This One Thing
Michael S. Palmer
Top 10 Lexus & Toyotas to Drive Before You Die!
Joe Kucinski
Top 10 Lexus/Toyotas With The LEAST 5-Year Depreciation
Joe Kucinski
Lexus LC500 Convertible Auction: A Preview of Rising Values?
Brett Foote
Rookie
Joined: Sep 2008
Posts: 86
Likes: 0
From: TN
Compression should be 178psi or more on a warm engine. Minimum should be 142psi on a warm engine. 14psi max variation between cylinders.
Your compression may be slightly low since you will be trying to do this on a cold engine. If you notice any cylinders that are significantly low try pouring a cap full of oil in them and redo the test. If compression comes up with oil in the cylinders then your rings/cylinders are fried. If not then you have a blown headgasket or leaky valves due to a misaligned timing belt or burnt valves. (This is unlikely, but possible)
I would also suggest testing the resistance of your coils, cam position sensors and crankshaft position sensor.
Ignition coil:
Primary
Cold - 0.36-0.55Ω
Hot - 0.45-0.65Ω
Secondary
Cold - 9.0-15.4kΩ
Hot - 11.4-18.1kΩ
Cam Position Sensor:
Cold 835 - 1,400Ω
Hot 1,060 - 1,645Ω
Crankshaft Position Sensor:
Cold 835 - 1,400Ω
Hot 1,060 - 1,645Ω
Since you'll be working on a cold engine, use the cold values listed above.
Python is correct about weak/incorrect sparking. Just because you have spark when the plugs are out of the engine, doesn't mean that they have spark in the cylinder while under compression. Your starting fluid test would indicate that this may be the case provided that your timing isn't off.
Report back what you find.
Your compression may be slightly low since you will be trying to do this on a cold engine. If you notice any cylinders that are significantly low try pouring a cap full of oil in them and redo the test. If compression comes up with oil in the cylinders then your rings/cylinders are fried. If not then you have a blown headgasket or leaky valves due to a misaligned timing belt or burnt valves. (This is unlikely, but possible)
I would also suggest testing the resistance of your coils, cam position sensors and crankshaft position sensor.
Ignition coil:
Primary
Cold - 0.36-0.55Ω
Hot - 0.45-0.65Ω
Secondary
Cold - 9.0-15.4kΩ
Hot - 11.4-18.1kΩ
Cam Position Sensor:
Cold 835 - 1,400Ω
Hot 1,060 - 1,645Ω
Crankshaft Position Sensor:
Cold 835 - 1,400Ω
Hot 1,060 - 1,645Ω
Since you'll be working on a cold engine, use the cold values listed above.
Python is correct about weak/incorrect sparking. Just because you have spark when the plugs are out of the engine, doesn't mean that they have spark in the cylinder while under compression. Your starting fluid test would indicate that this may be the case provided that your timing isn't off.
Report back what you find.
Thread Starter
Driver School Candidate
Joined: Mar 2009
Posts: 12
Likes: 0
From: Indiana
Ok I will check compression. I know where the coils are located, I have a volt ohm meter now how do I test them? Not sure where the cam sensor or crankshaft sensors are and how do I test those? Thanks alot for all the help
Thread
Thread Starter
Forum
Replies
Last Post
Push
LS - 1st and 2nd Gen (1990-2000)
11
Dec 17, 2012 07:25 AM
